'@' mentions for users does not work

**Describe the bug**
When I use @user.name, it comes out as plain text in the JIRA UI. When I fetch an issue with an At mentioned member, I see the user prefixed with `/~`, However when I try to also put in `/~user.name` it comes out as plain text in the UI and `\/~user.name` in my `jira-cli`.

**Please provide following details**
1. JiraCLI Version:
```
(Version="v1.0.0", GitCommit="", CommitDate="", GoVersion="go1.18.3", Compiler="gc", Platform="darwin/arm64")
```
2. Are you using Jira cloud or on-premise jira server? Also mention the version for on-premise installation.
```
v8.13.20#813020
```
3. What operating system are you using? Also mention version.
```
macOS Montery 12.4
```
4. What terminal are you using? Also mention version.
```
MacOS Terminal w/ `zsh`
```

**To Reproduce**

Steps to reproduce the behavior:
1. `jira issue create`
2. try to @user.name` mention someone in the description or comments
3. notice that the user is not @ mentioned and the `@user.name` is plain text

**Expected behavior**
@ mention binds to a user and notifies them as in the JIRA UI.